Physical activity correlates in adolescent girls who differ by weight status

[Does nutritional status moderate the association between social support, self-efficacy, and physical activity time of adolescents?]

The scope of this paper is to analyze the association between social support, self-efficacy and practice time of physical activity of different intensity (light, moderate, vigorous) and evaluate if these associations are moderated by the nutritional status of adolescents. It involved a cross-sectional study with 650 adolescents (10-14 years old, 52.9% female) from João Pessoa, State of Paraíba. Social support was measured by a scale with five items for each source of support (father, mother and friends) and self-efficacy, with a scale of four items. The physical activity time was measured by means of an accelerometer and the nutritional status was assessed by body mass index. The results of the multiple linear regression analysis showed that social support of friends was positively and significantly associated with moderate intensity physical activity time (β=2.67; CI95%: 0.28; 5.07). The nutritional status did not moderate the association of social support and self-efficacy with the duration of physical activity (p>0.05). The conclusion drawn is that adolescents who perceived that they are receiving more social support from friends tend to practice more moderate intensity physical activity, irrespective of their nutritional status.

A Dyadic Analysis on Source Discrepancy and a Mediation Analysis via Self-Efficacy in the Parental Support and Physical Activity Relationship among Black Girls

BACKGROUND

Physical activity (PA) declines in adolescence among black girls. This study assesses how moderate/vigorous physical activity (MVPA) relates to caregiver- vs. adolescent-reported parental support and whether the relationship is mediated by self-efficacy.

METHODS

MVPA was assessed through accelerometry. Parental support and encouragement on adolescents' PA were reported by caregivers and adolescents with a 10-item Social Support and Exercise Survey. Adolescent-reported self-efficacy related to PA was assessed with an 8-item scale. Structural equation modeling assessed source variation (caregiver vs. adolescent report) in the relationship between parental support and MVPA and mediation through adolescent self-efficacy.

RESULTS

The sample includes black adolescent girls (n = 272), with mean age of 11.6 years (standard deviation = 0.7), and average MVPA/day of 40.6 minutes. Caregiver/adolescent agreement on parental support was low (weighted Kappa <0.20). There was significant source variation in the parental support-MVPA relationship (Wald χ² = 4.18, df = 1, p = 0.041); adolescent-reported support was related to MVPA (b = 0.40, standard error = 0.14, p = 0.003) and mediated through self-efficacy (95% bootstrapped confidence interval: 0.05-0.29). Caregiver-reported support or BMI z-score was not related to MVPA.

CONCLUSIONS

The association between MVPA and adolescent-reported parental support among black adolescent girls is explained by positive self-efficacy. Findings suggest that effective adolescent/caregiver communication around parental support on PA relates to high adolescent self-efficacy and supports objectively measured PA. Additional research is merited to examine longitudinal patterns. Furthermore, although 51.5% of girls in the sample were overweight or obese, the lack of association between MVPA and body composition minimizes its implication for mitigating obesity among overweight/obese black adolescent girls.

Socio-Cultural and Environmental Factors that Influence Weight-Related Behaviors: Focus Group Results from African-American Girls and Their Mothers

African-American girls experience higher rates of obesity than other youth and are more likely to live in environments that may inhibit healthy lifestyles. Focus groups with African-American girls (14.2 ± 2.36 years) and their mothers were conducted to explore socio-cultural and physical factors within the home, neighborhood, and school environments that influence physical activity (PA) and food choices (i.e., availability and accessibility). Being active at home was dependent on availability of unstructured PA, possibility of activity with family/friends/pet, structured sports in the community, and perceived safety of neighborhood. Girls reported unhealthy foods and excessive snacking as issues at home while citing choice of school meals vs. vending machine items and easy accessibility to fast food restaurants as concerns at school. Learning more about the PA and food environments is a fundamental step to develop effective and innovative, environmental strategies to address unhealthy weight-related behaviors in this population.

Effectiveness of mother and daughter interventions targeting physical activity, fitness, nutrition and adiposity: A systematic review

BACKGROUND

Physical inactivity and poor dietary habits in women pose a clear public health burden. Mothers are generally the main female role model for daughters, therefore, targeting intergenerational females simultaneously may be a novel approach. However, the effectiveness of this approach to improve physical activity, fitness, nutrition and adiposity has not been systematically examined.

OBJECTIVES

To assess the effectiveness of physical activity, fitness and nutrition interventions targeting mothers and their daughters.

DATA SOURCES

PubMed, Psychinfo, EMBASE, Ovid Medline, SCOPUS, CINAHL, Sportdiscus and Informit were searched for English language studies (1980-2015).

STUDY SELECTION

Randomized controlled trials (RCTS), non-randomized experimental trials and pre-post studies of physical activity, fitness, nutrition and adiposity interventions targeting mothers and daughters were eligible if they reported changes in physical activity, fitness, dietary intake or adiposity.

DATA EXTRACTION

Data were extracted using a standardized template and checked by a second author.

DATA SYNTHESIS

3577 articles were screened and 14 unique studies (7 RCTs, 1 pseudo-randomized, 1 non-randomized, 5 pre-post) met the inclusion criteria. The majority of studies were conducted in the US (n=11) and most were limited by methodological concerns. Of the RCTs that targeted each outcome exclusively, ≤20%, ≤20% ≤21% and 0% were successful for improving physical activity, fitness, nutrition and adiposity respectively.

CONCLUSIONS

Overall, evidence for the effectiveness of mother-daughter interventions to improve physical activity, fitness, nutrition and adiposity is inconclusive. The diversity of study designs, exposures and outcomes used, along with methodological weaknesses means that well-designed and reported RCTs are warranted.

Correlates of Social Support and its Association With Physical Activity Among Young Adolescents

BACKGROUND

A substantial proportion of adolescents, particularly girls and minority youth, fail to meet daily physical activity (PA) recommendations. Social support contributes to adolescent PA, but studies examining this relationship have yielded inconsistent results and rarely focus on diverse, urban populations.

AIMS

This study examines the correlates of support for PA from family and friends and its relationship with PA outcomes among young adolescents.

METHODS

Data were collected in a cross-sectional survey of 4,773 middle school students. Social support from family and friends was separately measured using the Sallis Support for Exercise Scales. Hierarchical logistic regression models were used to assess correlates of high support and the relationship between support and self-reported PA.

RESULTS

Approximately one quarter of students reported being active for at least an hour each day. 31.7% of students reported high family support for PA, while 17.8% reported high friend support. Differences in perceptions of support by gender, ethnicity, and language emerged. Support from family and friends were both consistently strong predictors of all three PA outcomes measured.

DISCUSSION

Findings highlight the need for multilevel interventions targeting both psychosocial influences on behavior in addition to addressing the physical environment. Given low rates of friend support for PA, there appears to be an opportunity to increase PA levels through promotion of supportive behaviors among peers.

CONCLUSION

Support for PA from family and friends is a key contributor to increased PA among adolescents. Further research is needed to further understand the mechanisms by which these factors influence PA.

Factors related to obesity and overweight among Black adolescent girls in the United States

In the United States, Black adolescents have the highest prevalence of pediatric obesity and overweight among girls. While Black girls are disproportionately affected, the reasons for this health disparity remain unclear. The authors conducted a systematic review to investigate the factors related to obesity and overweight among Black adolescent girls. The authors searched four databases for relevant English-language publications using all publication years through 2015. Fifty-one studies met the inclusion criteria and were used for this review. Using a configuration approach to synthesis, three categories were identified, paralleling the bioecological theory of human development: (1) individual, (2) interpersonal, and (3) community and societal factors. A description of each factor's association with obesity among Black adolescent girls is presented. From this review, the authors identified a diverse and vast set of individual, interpersonal, and community and societal factors explored for their relationship with obesity and overweight. Given the insufficient repetition and limited significant findings among most factors, the authors believe that multiple gaps in knowledge exist across all categories regarding the factors related to obesity and overweight among Black adolescent girls. To improve the quality of research in this area, suggested research directions and methodological recommendations are provided.

Relations of Neighborhood Environment Influences, Physical Activity, and Active Transportation to/from School across African American, Latino American, and White Girls in the United States

BACKGROUND

Neighborhood environment influences may be particularly important for understanding physical activity (PA) patterns across ethnic subgroups of early adolescent girls.

PURPOSE

This study examined relationships between neighborhood variables, moderate to vigorous physical activity (MVPA), and active transportation to/from school across African American, Latino American, and White early adolescent girls living in an urban/suburban community in the northwestern U.S.A. Relations between the neighborhood variables across ethnic groups also were examined.

METHOD

The sample comprised 372 African American, Latino American, and White girls living in the U.S.A. (mean age = 12.06 years; SD = 1.69).

RESULTS

Data were analyzed using multiple-sample structural equation modeling. Results showed that girls' MVPA was positively related to physical activity facility accessibility and negatively related to age. Active transport was positively related to physical activity facility accessibility, neighborhood walkability, and age, and negatively related to distance to the nearest school and household income.

CONCLUSIONS

Findings highlight the importance of both perceived and objective neighborhood influences on girls' MVPA and active transport. Consistencies in findings across African American, Latino American, and White girls suggest that neighborhood-level PA promotion has the potential for broad impact across all three ethnic groups.

Enjoyment, Barriers, and Beliefs About Physical Activity in Adolescents With and Without Autism Spectrum Disorder

The authors compared physical activity enjoyment, perceived barriers, beliefs, and self-efficacy between adolescents with autism spectrum disorder (ASD) and typically developing (TD) adolescents. A questionnaire was verbally administered to 35 adolescents with ASD and 60 TD adolescents. Compared with TD adolescents, fewer adolescents with ASD enjoyed team sports (65% vs. 95%, p < .001) and physical education (84% vs. 98%, p = .02). A greater proportion of adolescents with ASD perceived that physical activities were too hard to learn (16% vs. 0%, p < .01), and fewer believed that physical activity was a way to make friends (68% vs. 97%, p < .001). Fewer adolescents with ASD preferred to do physical activity in their free time (25% vs. 58%, p < .01). Most adolescents with ASD felt that physical activity is fun (84%), but the proportion was lower than in TD adolescents (98%, p = .03). Some perceptions about physical activity were similar between the 2 groups, but differences identified may inform program development.

Quantitative physical activity assessment of children and adolescents in a rural population from Eastern Nepal

OBJECTIVES

We report cross-sectional, objectively measured physical activity data for 399 children and adolescents aged 6 to 18 years. We evaluated physical activity of children and adolescents, considered time spent in each activity intensity category, and explored the impact of growth disruption (stunting and wasting) on physical activity patterns.

METHODS

Participants wore an Actical (Mini-Mitter, Bend, OR) omnidirectional accelerometer for one week as part of their annual visit to the Jiri Growth Study. The percentage of time spent in standard activity intensities were computed using standard metabolic equivalents (METS) cutpoints and compared by chronological age, sex, and school versus non-school days.

RESULTS

Primary findings include (1) children are more active on non-school days and adolescents are more active during the school week; (2) Jirel children do not exhibit the reduction in physical activity that most Western populations experience during the transition from childhood to adolescence; and (3) Jirel children and adolescents routinely meet the suggested one hour/day MVPA threshold; (4) Stunting is prevalent and factors leading to this growth disruption may contribute to the amount of time in sedentary or light physical activity.

CONCLUSIONS

We report child and adolescent physical activity patterns from the Jirel population of eastern Nepal. In this rural context, children and adolescents are more active than populations reported from Western contexts. This key finding has important biomedical implications for the maintenance of healthy body composition, skeletal health, and other health traits.

Including Youth with Intellectual Disabilities in Health Promotion Research: Development and Reliability of a Structured Interview to Assess the Correlates of Physical Activity among Youth

BACKGROUND

The input of youth with intellectual disabilities in health promotion and health disparities research is essential for understanding their needs and preferences. Regular physical activity (PA) is vital for health and well-being, but levels are low in youth generally, including those with intellectual disabilities. Understanding the perceptions of and barriers to PA as reported by youth with intellectual disabilities themselves is important for designing effective interventions.

MATERIALS AND METHODS

We developed a structured interview that queried youth with intellectual disabilities and typically developing youth (ages 13-21 years) about their enjoyment, preferences and perceived barriers to PA. We describe the development of this interview and present its test-retest reliability on 15 youth with intellectual disabilities and 20 typically developing youth.

RESULTS

Twenty-three of 33 questions were reliable in both groups. The results suggest that youth with intellectual disabilities can reliably report activities that they do or do not enjoy, as well as their beliefs and perceived benefits of PA.

CONCLUSIONS

Self-reported information on the experiences, preferences, beliefs and perceptions about among youth with intellectual disabilities is key for research efforts in health promotion and health disparities.

Factors Associated With Healthy Lifestyle Behaviors in a Sample of Turkish Adolescents: A School-Based Study

PURPOSE

This was a descriptive-correlational study designed to determine factors associated with the healthy lifestyle behaviors of high school students in Turkey.

DESIGN

The study sample consisted of 812 high school adolescents. The Adolescent Lifestyle Profile scale was used to identify the healthy lifestyle behaviors of adolescents.

RESULTS

The total Adolescent Lifestyle Profile mean score of 2.75 ± 0.33 and the mean score on the Interpersonal relations subscale were found to be the highest scores while the mean score on the Health responsibility subscale was found to be the lowest. Significant predictors of healthy lifestyle behaviors of adolescents were good relationships with family and friends, having a father who was a college graduate, and good health perception.

CONCLUSIONS

The study revealed similar results among adolescents of different cultures.

IMPLICATIONS FOR PRACTICE

These findings can be used as a guide in developing an adolescent health promotion program for school nurses.

Physical Activity Enjoyment, Perceived Barriers, and Beliefs Among Adolescents With and Without Intellectual Disabilities

BACKGROUND

Youths with intellectual disabilities (ID) exhibit low levels of physical activity, but the underlying contributors to behavior are unclear. We compared physical activity enjoyment, perceived barriers, beliefs, and self-efficacy among adolescents with ID and typically developing (TD) adolescents.

METHODS

A questionnaire was administered to 38 adolescents with ID (mean age, 16.8 years) and 60 TD adolescents (mean age, 15.3 years). Of the original 33 questionnaire items, 23 met the test-retest reliability criteria and were included in the group comparisons.

RESULTS

Fewer adolescents with ID reported that they have someone with whom to do physical activity (64% vs 93%: P < .001), and a greater percentage of adolescents with ID perceived that physical activities were too hard to learn (41% vs 0%; P < .001). Fewer adolescents with ID believed that physical activity would be good for their health (92% vs 100%; P = .05). More adolescents with ID reported a dislike of individual physical activities (P = .02). A large percentage of adolescents with ID (84%) responded that they were good at doing physical activities, but the difference between groups was only of borderline significance (95% of TD adolescents, P = .06).

CONCLUSIONS

Adolescents shared many of the same perceptions about physical activity, but some important differences between groups were identified.

Weight status as a moderator of the relationship between motivation, emotional social support, and physical activity in underserved adolescents

OBJECTIVE

This study examined weight status as a moderator of the relationship between motivation (controlled, autonomous, regulatory), emotional social support (parents, peers) and moderate-to-vigorous physical activity (MVPA) in underserved adolescents (ethnic minority, low-income).

METHODS

Participants from the Active by Choice Today Trial (n = 1,416; 54% girls, 73% African American, 52% overweight/obese) completed baseline measures, including height and weight, psychosocial surveys, and 7-day accelerometry estimates. Weight status was defined by body mass index z-score (zBMI).

RESULTS

Weight status moderated the effects of controlled, autonomous, and regulatory motivation on MVPA, such that these variables were more strongly associated with MVPA in adolescents with lower versus higher zBMI scores.

CONCLUSIONS

A better understanding of why motivation is not related to MVPA in underserved youth with a higher weight status is needed. Future pediatric obesity treatment in underserved youth may need to move beyond motivation into environmental factors associated with long-term behavior change.

Association between sedentary behaviour and socioeconomic factors, diet and lifestyle among the Balearic Islands adolescents

BACKGROUND

Many different factors influenced food habits and physical activity patterns of adolescents in a complex interactive way. The aim of this study was to assess association between sedentary behaviour and socioeconomic factors, diet and lifestyle among the Balearic Islands adolescents.

METHODS

A cross-sectional survey (n = 1961; 12-17 years old) was carried out. Physical activity was assessed using the International Physical Activity Questionnaire for adolescents (IPAQ-A). Sedentary behaviour was defined as <300 min/week of moderate and vigorous physical activity. Anthropometric measurements, body image, socio-economic and lifestyle determinants, food consumption, and adherence to the Mediterranean diet were assessed.

RESULTS

The prevalence of sedentary behaviour was 37.1% (22.0% boys, 50.8% girls). Active boys consumed frequently breakfast cereals and fresh fruit; active girls yogurt, cheese, breakfast cereals, and fresh fruit; and sedentary girls high fat foods and soft drinks. Sedentary behaviour of girls was directly associated to age, and time spent on media screen and homework, and inversely related to adherence to Mediterranean diet, and body composition. Sedentary behaviour of boys was inversely related to adherence to the Mediterranean diet, and the desire to remain the same weight.

CONCLUSIONS

The prevalence of sedentary behaviour among Balearic Islands adolescents is high, mainly among girls. Age, sex, parental educational and profession levels, body size dissatisfaction, and poor quality diet are important factors of physical activity practice among adolescents.

Do peers matter? A review of peer and/or friends' influence on physical activity among American adolescents

This systematic review investigated the relationship between peer and/or friend variables and physical activity among adolescents by synthesising cross-sectional, longitudinal, and experimental research conducted in the US. Seven electronic databases were searched to identify related articles published within the last 10 years and the articles reviewed included adolescents between 10 and 18 years. Studies reporting a measure of physical activity for adolescents and at least one potential peer and/or friend variable were included. Research demonstrated that peers and friends have an important role to play in the physical activity behavior of adolescents. Six processes were identified through which peers and/or friends may have an influence on physical activity including: peer and/or friend support, presence of peers and friends, peer norms, friendship quality and acceptance, peer crowds, and peer victimization. The theoretical significance of these results is assessed and the development of peer-related physical activity programs for adolescents is discussed.

Do youth sports prevent pediatric obesity? A systematic review and commentary

Sport is a promising setting for obesity prevention among youth, but little is known about whether it prevents obesity. We reviewed research comparing sport participants with nonparticipants on weight status, physical activity, and diet. Among 19 studies, we found no clear pattern of association between body weight and sport participation. Among 17 studies, we found that sport participants are more physically active than those who do not participate. We found seven studies that compared the diet of sport participants with non-participants. These studies reported that youth involved in sport were more likely to consume fruits, vegetables, and milk, and also more likely to eat fast food and drink sugar-sweetened beverages and consume more calories overall. It is unclear from these results whether sports programs, as currently offered, protect youth from becoming overweight or obese. Additional research may foster understanding about how sport, and youth sport settings, can help promote energy balance and healthy body weight.

Intrapersonal, behavioral, and environmental factors associated with meeting recommended physical activity among rural Latino youth

This study aimed to identify intrapersonal, behavioral, and environmental factors associated with engaging in recommended levels of physical activity among rural Latino middle school youth. Data were from an anonymous survey of 773 Latino youth (51% female) about level of and barriers and motivators to physical activity, risk behaviors, and park use. Logistic regression models identified factors correlated with meeting recommended levels of physical activity (5 days or more 3 60 min/day). Thirty-four percent of girls and 41% of boys reported meeting this physical activity recommendation. Participation in an organized after school activity (p < .001) and in physical education (PE) classes 5 days a week (p < .001) were strongly associated with meeting recommended physical activity level. Making PE available 5 days a week and creating opportunities for organized after school physical activity programs may increase the number of rural Latino middle school youth who meet recommended physical activity level.

Body mass index and the built and social environments in children and adolescents using electronic health records

BACKGROUND

No prior studies in children have evaluated how age may modify relationships of the built and social environments with BMI, nor evaluated the range of scales and contexts over which places may influence health.

PURPOSE

To systematically evaluate associations of 33 environmental measures in three domains (land use, physical activity, and social environments) with BMI in children and adolescents in five geographies.

METHODS

A cross-sectional, multilevel analysis was completed in 2009-2010 of electronic health record data (2001-2008) from 47,769 children aged 5-18 years residing in a 31-county region of Pennsylvania. Associations of environmental measures with BMI were evaluated using 0.5-mile network buffers; census tracts; minor civil divisions (i.e., townships, boroughs, cities); a mixed definition of place (townships, boroughs, and census tracts in cities); and counties, overall and by age strata.

RESULTS

Among all children, lower levels of community socioeconomic deprivation and greater diversity of physical activity establishments were associated with lower BMI. Associations of environmental measures differed by age, depending on scale and context. For example, higher population density was associated with lower BMI in older children; this effect was strongest in the larger geographies. Similarly, a lower level of county sprawl was associated with lower BMI in older children.

CONCLUSIONS

Associations differed by age and definition of place, suggesting that the benefits of environmental intervention may not be uniform across the childhood age range. The study demonstrated the utility of using electronic patient information for large-scale, population-based epidemiologic research, a research area of growing interest and investment in the U.S.

Neighborhood environment and physical activity among youth a review

CONTEXT

Research examining the association between environmental attributes and physical activity among youth is growing. An updated review of literature is needed to summarize the current evidence base, and to inform policies and environmental interventions to promote active lifestyles among young people.

EVIDENCE ACQUISITION

A literature search was conducted using the Active Living Research (ALR) literature database, an online database that codes study characteristics and results of published papers on built/social environment and physical activity/obesity/sedentary behavior. Papers in the ALR database were identified through PubMed, Web of Science, and SPORTDiscus using systematically developed and expert-validated search protocols. For the current review, additional inclusion criteria were used to select observational, quantitative studies among youth aged 3-18 years.

EVIDENCE SYNTHESIS

Papers were categorized by design features, sample characteristics, and measurement mode. Relevant results were summarized, stratified by age (children or adolescents) and mode of measurement (objective or perceived) for environmental attributes and physical activity. Percentage of significant results was calculated.

CONCLUSIONS

Mode of measurement greatly influenced the consistency of associations between environmental attributes and youth physical activity. For both children and adolescents, the most consistent associations involved objectively measured environmental attributes and reported physical activity. The most supported correlates for children were walkability, traffic speed/volume, access/proximity to recreation facilities, land-use mix, and residential density. The most supported correlates for adolescents were land-use mix and residential density. These findings support several recommendations for policy and environmental change from such groups as the IOM and National Physical Activity Plan.

Neighborhood and parental supports for physical activity in minority adolescents

BACKGROUND

Few studies have examined environmental, home, and parental supports for physical activity in underserved adolescents (low income, ethnic minority). Given the increasing incidence of obesity in minority adolescents, it is important to better understand ecologic determinants of physical activity in these youth. This study used an ecologic model to evaluate the significance of neighborhood, home, and parental supports for physical activity on moderate-to-vigorous (MV) physical activity in underserved adolescents.

DESIGN

The study was a secondary data analysis of a randomized controlled school-based trial "Active by Choice Today" (ACT) for increasing physical activity in underserved sixth-graders. Schools were matched on school size, percentage minorities, percentage entitled to free or reduced-price lunch, and urban or rural setting prior to randomization. This study used a randomly selected sample of parents (n=280) from the intervention and control schools whose adolescent was enrolled in the larger trial.

SETTING/PARTICIPANTS

A total of 679 6th-grade students (mean age=11.4 years, 70% African-American, 76% free or reduced-price lunch, 52% female) participated in the larger trial. Parents of 280 youth were contacted to participate in a telephone survey and 198 (71%) took part in the study.

INTERVENTIONS

The ACT trial was designed to test the efficacy of a 17-week (1 academic year) motivational plus behavioral skills intervention versus comparison after-school programs on increasing physical activity. A telephone survey was developed and was administered within 6 months after the trial began on parents of 198 adolescents from the ACT randomized school-based trial during 2005-2007.

MAIN OUTCOME MEASURES

The primary outcome measure was adolescent MVPA based on 7-day accelerometry estimates from baseline to mid-intervention. The data were analyzed in 2010-2011 and included both parent and adolescent self-reports of environmental, home, and family supports for physical activity.

RESULTS

Regression analyses indicated a significant effect of parental and neighborhood supports for physical activity on adolescent MVPA. Adolescents who perceived higher (vs lower) levels of parental support for physical activity engaged in more minutes of MVPA (B=3.01, SE=1.38, p<0.05) at mid-intervention. Adolescents who lived in neighborhoods with more (vs fewer) supports for physical activity (parks, lighting), also engaged in more minutes MVPA (B=4.27, SE=2.15, p<0.05).

CONCLUSIONS

Support from parents and neighborhood quality are both associated with increased physical activity in underserved adolescents.

Parent-child relationship of directly measured physical activity

BACKGROUND

Studies on parent-child correlations of physical activity have been mixed. Few studies have examined concurrent temporal patterns of physical activity and sedentary behaviors in parents and children using direct measures. The purpose of this study was to examine parent-child activity correlations by gender, day of week, and time of day, using accelerometers - a method for direct assessment of physical activity.

METHODS

Accelerometers were used to assess physical activity and sedentary time in 45 fathers, 45 mothers and their children (23 boys, 22 girls, mean age 9.9 years) over the course of 4 days (Thursday - Sunday). Participants were instructed to wear accelerometers for 24 hours per day. Data from accelerometers were aggregated into waking hours on weekdays and weekends (6:00 am to midnight) and weekday after-school hours (3:00 - 7:00 pm).

RESULTS

Across the 4 days, the mean minutes per day of moderate-to-vigorous physical activity (MVPA) for fathers was 30.0 (s.d. = 17.3), for mothers was 30.1 (s.d. = 20.1) and for children was 145.47 (s.d. = 51.64). Mothers' and fathers' minutes of MVPA and minutes of sedentary time were positively correlated with child physical activity and sedentary time (all ps < .05, with the exception of mothers' and children's sedentary time on weekdays from 6 am to 12 am). Multivariate linear regression analyses resulted in significant effects between parents and children for MVPA across all time segments. For sedentary activity, significant associations were observed only between father and child on the weekend. Sedentary activity of parents and children were not related for other time segments. Models examining the associations of one or two parents with high levels of MVPA or sedentary time indicated a dose response increase in child activity relative to parent.

CONCLUSIONS

Greater parental MVPA was associated with increased child MVPA. In addition, having two parents with higher levels of MVPA was associated with greater levels of activity in children. Sedentary time in children was not as strongly correlated with that of their parents. Findings lend support to the notion that to increase childhood activity levels it may be fruitful to improve physical activity among parents.

Parental social support and the physical activity-related behaviors of youth: a review

Social support from parents serves as one of the primary influences of youth physical activity-related behaviors. A systematic review was conducted on the relationship of parental social support to the physical activity-related behaviors of youth. Four categories of social support were identified, falling under two distinct mechanisms-tangible and intangible. Tangible social support is divided into two categories: instrumental-purchasing equipment/payment of fees and transportation-and conditional-doing activity with and watching/supervision. Intangible social support is divided into the two categories of motivational- encouragement and praise-and informational-discussing benefits of. The majority of studies demonstrated positive associations among selected measures of parental tangible and intangible social support and youth activity. Overall, parental social support demonstrated positive effects. Many studies, however, combine social support categories and/or respondents into composite measures, making it difficult to disentangle the specific effects of parents and the type of support provided.

Transition in participation in sport and unstructured physical activity for rural living adolescent girls

Physical activity (PA) is important for lifelong health; however, participation is lower in rural compared with metropolitan areas and declines during adolescence, particularly for girls. It is likely that this decline is related to the number of life transitions that occur during adolescence. This qualitative study examined the views of active rural living girls regarding the factors affecting their sport and PA participation, using the socioecological model. Twenty-seven girls aged 16-17 from four schools participated in semi-structured focus group discussions. Content and thematic analysis was conducted from verbatim transcripts using NVivo. The girls enjoyed involvement in community club sport with friends and they reported living in communities where participation in sport was a major form of social interaction. However, the desire to succeed educationally was a critical factor affecting their participation in sport and PA and influenced their movement from structured club sport to more flexible, but socially isolated individual activities. It is recommended that future longitudinal research should track rural living adolescent females as they complete secondary school, in order to better understand the influence of educational priorities upon sport and PA participation and to identify practical strategies for both schools and community organizations to foster continuing participation throughout this crucial period of life transition.

The built environment and obesity: a systematic review of the epidemiologic evidence

We completed a systematic search of the epidemiologic literature on built environment and obesity and identified 63 relevant papers, which were then evaluated for the quality of between-study evidence. We were able to classify studies into one of two primary approaches for defining place and corresponding geographic areas of influence: those based on contextual effects derived from shared pre-determined administrative units and those based on individually unique geographic buffers. The 22 contextual papers evaluated 80 relations, 38 of which did not achieve statistical significance. The 15 buffer papers evaluated 40 relations, 24 of which did not achieve statistical significance. There was very little between-study similarity in methods in both types of approaches, which prevented estimation of pooled effects. The great heterogeneity across studies limits what can be learned from this body of evidence.

Disparities in physical activity and sedentary behaviors among US children and adolescents: prevalence, correlates, and intervention implications

Regular physical activity is important for health benefits among youth, but disparities exist. This paper describes disparities in physical activity participation and sedentary behaviors among youth in the United States, provides intervention implications, and offers recommendations for future research focused on reducing disparities related to levels of physical activity. Secondary analysis of national accelerometer data showed that achievement of recommended levels of physical activity ranged across subgroups from 2% to 61%. Mean hours per day spent in sedentary behavior ranged from 5.5 to 8.5. The largest disparities were by gender and age. An improved understanding of correlates may inform the design of interventions to increase physical activity in targeted subgroups. Additional theoretically based research is needed to elucidate which factors contributing to physical activity disparities are amenable to change via intervention. To eliminate health disparities, changes in policies that have an impact on physical activity may be necessary to promote physical activity among high-risk youth.

Association between neighborhood safety and overweight status among urban adolescents

Background

Neighborhood safety may be an important social environmental determinant of overweight. We examined the relationship between perceived neighborhood safety and overweight status, and assessed the validity of reported neighborhood safety among a representative community sample of urban adolescents (who were racially and ethnically diverse).

Methods

Data come from the 2006 Boston Youth Survey, a cross-sectional study in which public high school students in Boston, MA completed a pencil-and-paper survey. The study used a two-stage, stratified sampling design whereby schools and then 9^th–12^th grade classrooms within schools were selected (the analytic sample included 1,140 students). Students reported their perceptions of neighborhood safety and several associated dimensions. With self-reported height and weight data, we computed body mass index (BMI, kg/m²) for the adolescents based on CDC growth charts. Chi-square statistics and corresponding p-values were computed to compare perceived neighborhood safety by the several associated dimensions. Prevalence ratios (PRs) and 95% confidence intervals (CI) were calculated to examine the association between perceived neighborhood safety and the prevalence of overweight status controlling for relevant covariates and school site.

Results

More than one-third (35.6%) of students said they always felt safe in their neighborhood, 43.9% said they sometimes felt safe, 11.6% rarely felt safe, and 8.9% never felt safe. Those students who reported that they rarely or never feel safe in their neighborhoods were more likely than those who said they always or sometimes feel safe to believe that gang violence was a serious problem in their neighborhood or school (68.0% vs. 44.1%, p < 0.001), and to have seen someone in their neighborhood assaulted with a weapon (other than a firearm) in the past 12 months (17.8% vs. 11.3%, p = 0.025). In the fully adjusted model (including grade and school) stratified by race/ethnicity, we found a statistically significant association between feeling unsafe in one's own neighborhood and overweight status among those in the Other race/ethnicity group [(PR = 1.56, (95% CI: 1.02, 2.40)].

Conclusion

Data suggest that perception of neighborhood safety may be associated with overweight status among urban adolescents in certain racial/ethnic groups. Policies and programs to address neighborhood safety may also be preventive for adolescent overweight.

Physical environmental correlates of childhood obesity: a systematic review

Increasing rates of childhood obesity in the USA and other Western countries are a cause for serious public health concern. Neighborhood and community environments are thought to play a contributing role in the development of obesity among youth, but it is not well understood which types of physical environmental characteristics have the most potential to influence obesity outcomes. This paper reports the results of a systematic review of quantitative research examining built and biophysical environmental variables associated with obesity in children and adolescents through physical activity. Literature searches in PubMed, PsychInfo and Geobase were conducted. Fifteen quantitative studies met the inclusion criteria for this systematic review. The majority of studies were cross-sectional and published after 2005. Overall, few consistent findings emerged. For children, associations between physical environmental variables and obesity differed by gender, age, socioeconomic status, population density and whether reports were made by the parent or child. Access to equipment and facilities, neighborhood pattern (e.g. rural, exurban, suburban) and urban sprawl were associated with obesity outcomes in adolescents. For most environmental variables considered, strong empirical evidence is not yet available. Conceptual gaps, methodological limitations and future research directions are discussed.

Influences of physical and social neighborhood environments on children's physical activity and obesity

OBJECTIVES

We investigated the association between physical and social neighborhood environments and fifth-grade students' physical activity and obesity.

METHODS

We collected data on 650 children and their primary caregivers during phase 1 of Healthy Passages, a multisite, community-based, cross-sectional study of health risk behaviors and health outcomes in children. We conducted independent systematic neighborhood observations to measure neighborhood physical characteristics, and we analyzed survey data on social processes. We modeled children's physical activity and obesity status with structural equation models that included latent variables for the physical and social environments.

RESULTS

After we controlled for children's sociodemographic factors, we found that a favorable social environment was positively associated with several measures of physical activity and that physical activity was negatively associated with obesity in these children. Physical environment was not significantly associated with physical activity.

CONCLUSIONS

Our findings suggest that neighborhood social factors as well as the physical environment should be considered in the development of health policy and interventions to reduce childhood obesity.